WordPress permalinks affect the structure of URLs on your website. If the date provides context for your content like if you're running news site you might want to use one of the options that includes the in URL, instead... To set your slug, look for the Permalink in Document of WordPress editor. the in URL box is what will come after your domain name, and you can see preview of URL below that box.. any links to your existing content will stop working because URLs of your existing content will change... That means you might miss out on traffic from media, and it also means you might lose SEO benefit of any links pointing to your old permalink structure... To fix this, you can use 301 redirect to redirect humans and search engine bots to the right spot when they visit one of your old links. you can use this free from Yoast to generate the proper 301 redirect code... Once you've set your permalink structure, you can edit URL slug for each post or page from WordPress editor... Finally, the common fix is to force WordPress to generate new.htaccess file by clicking Save Changes in Settings → Permalinks area...
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